我正在使用 http://javapapers.com/android/google-cloud-messaging-gcm-for-android-and-push-notifications/#comment-103785 开发 GCM 示例应用程序.
我无法注册 gcm 服务器。我收到以下错误。我用眼镜查了一下。但我找不到解决方案，所有的解决方案都是关于 jar 文件的。我已经完成了所有更改，但我做不到得到它。
错误
FATAL EXCEPTION: main
java.lang.NoClassDefFoundError: com.google.android.gms.gcm.GoogleCloudMessaging
com.sanjeev.integrationapp.RegisterActivity.registerGCM(RegisterActivity.java:80)
com.sanjeev.integrationapp.RegisterActivity$1.onClick(RegisterActivity.java:47)
at android.view.View.performClick(View.java:4084)
at android.view.View$PerformClick.run(View.java:16966)
at android.os.Handler.handleCallback(Handler.java:615)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4745)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
at dalvik.system.NativeStart.main(Native Method)
我的类代码如下
public class RegisterActivity extends Activity {
Button btnGCMRegister;
Button btnAppShare;
GoogleCloudMessaging gcm;
Context context;
String regId;
public static final String REG_ID = "regId";
private static final String APP_VERSION = "appVersion";
static final String TAG = "Register Activity";
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
context = getApplicationContext();
btnGCMRegister = (Button) findViewById(R.id.btnGCMRegister);
btnGCMRegister.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View arg0) {
if (TextUtils.isEmpty(regId)) {
regId = registerGCM();
Log.d("RegisterActivity", "GCM RegId: " + regId);
} else {
Toast.makeText(getApplicationContext(),
"Already Registered with GCM Server!",
Toast.LENGTH_LONG).show();
}
}
});
btnAppShare = (Button) findViewById(R.id.btnAppShare);
btnAppShare.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View arg0) {
if (TextUtils.isEmpty(regId)) {
Toast.makeText(getApplicationContext(), "RegId is empty!",
Toast.LENGTH_LONG).show();
} else {
Intent i = new Intent(getApplicationContext(),
MainActivity.class);
i.putExtra("regId", regId);
Log.d("RegisterActivity",
"onClick of Share: Before starting main activity.");
startActivity(i);
finish();
Log.d("RegisterActivity", "onClick of Share: After finish.");
}
}
});
}
public String registerGCM() {
// below line I am getting error
gcm = GoogleCloudMessaging.getInstance(this);
regId = getRegistrationId(context);
if (TextUtils.isEmpty(regId)) {
registerInBackground();
Log.d("RegisterActivity",
"registerGCM - successfully registered with GCM server - regId: "
+ regId);
} else {
Toast.makeText(getApplicationContext(),
"RegId already available. RegId: " + regId,
Toast.LENGTH_LONG).show();
}
return regId;
}
@SuppressLint("NewApi")
private String getRegistrationId(Context context) {
final SharedPreferences prefs = getSharedPreferences(
MainActivity.class.getSimpleName(), Context.MODE_PRIVATE);
String registrationId = prefs.getString(REG_ID, "");
if (registrationId.isEmpty()) {
Log.i(TAG, "Registration not found.");
return "";
}
int registeredVersion = prefs.getInt(APP_VERSION, Integer.MIN_VALUE);
int currentVersion = getAppVersion(context);
if (registeredVersion != currentVersion) {
Log.i(TAG, "App version changed.");
return "";
}
return registrationId;
}
private static int getAppVersion(Context context) {
try {
PackageInfo packageInfo = context.getPackageManager()
.getPackageInfo(context.getPackageName(), 0);
return packageInfo.versionCode;
} catch (NameNotFoundException e) {
Log.d("RegisterActivity","I never expected this! Going down, going down!" + e);
throw new RuntimeException(e);
}
}
private void registerInBackground() {
new AsyncTask<Void, Void, String>() {
@Override
protected String doInBackground(Void... params) {
String msg = "";
try {
if (gcm == null) {
gcm = GoogleCloudMessaging.getInstance(context);
}
regId = gcm.register(Config.GOOGLE_PROJECT_ID);
Log.d("RegisterActivity", "registerInBackground - regId: "
+ regId);
msg = "Device registered, registration ID=" + regId;
storeRegistrationId(context, regId);
} catch (IOException ex) {
msg = "Error :" + ex.getMessage();
Log.d("RegisterActivity", "Error: " + msg);
}
Log.d("RegisterActivity", "AsyncTask completed: " + msg);
return msg;
}
@Override
protected void onPostExecute(String msg) {
Toast.makeText(getApplicationContext(),
"Registered with GCM Server." + msg,
Toast.LENGTH_LONG)
.show();
}
}.execute(null, null, null);
}
private void storeRegistrationId(Context context, String regId) {
final SharedPreferences prefs = getSharedPreferences(
MainActivity.class.getSimpleName(), Context.MODE_PRIVATE);
int appVersion = getAppVersion(context);
Log.i(TAG, "Saving regId on app version " + appVersion);
SharedPreferences.Editor editor = prefs.edit();
editor.putString(REG_ID, regId);
editor.putInt(APP_VERSION, appVersion);
editor.commit();
}
最佳答案
在这里，无需在您的工作区中导入 google_play_services_lib，google_play_services_lib 有一个名为 google-play-services.jar 的 jar，需要包含在您的 GCM 应用程序中。
google-play-services.jar 包含所有 GCM 相关类，这就是为什么 google_play_services_lib 被添加为对 GCM Android 项目的依赖。您可以做的最简单的事情是在您的 GCM 项目中添加该 jar，而不是添加 google_play_services_lib 项目的依赖项。
要在 android 项目中添加 jar，你必须执行以下操作，
1. 首先在你的项目下创建一个libs文件夹，它是一个libs文件夹，而不是lib。
2. 然后将google-play-services.jar复制到libs文件夹中。
3. 然后右键点击 google-play-services.jar 并选择 Build Path > Add to Build Path。
您可以看到在项目的根文件夹下创建的 Android 私有(private)库 将包含此 jar。
注意:jar 文件的路径 - sdk\extras\google\google_play_services\libproject\google-play-services_lib\libs
关于android - java.lang.NoClassDefFoundError : com. 谷歌.android.gms.gcm.GoogleCloudMessaging，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/23675699/